I were using winscpnet for file downloading. now i needed to support file resume funtionality. For that what i have done is
var options = new TransferOptions();
options.ResumeSupport.State = TransferResumeSupportState.On;

Now to check if file resume work I disconnect while downloading. Problem is that every time I now download it starts from zero instead of the place where it left. Like for 100 mb file if local downloaded length is 30 mb. when i try to reconnect it starts from zero length.